Evaporator for refrigerators



June 1, *19374 I A, PHILIPP Re. 20,388

` EVAPORATOR FOR REFRIGERATORS.

ReiuedJune l, 1937 i H I R i I 20,388 I EVAPOR ATOR FOR -REFRIGERATOR Lawrence A. Philip Detroit, Mich., assigor to Kelvinator Corporation, Detroit, Micl., a. corporation oi' Michigan *Original No. 1393338, dated January 3', 1933, 'Serial No. 354320, April 11, 1929. Applicaiznsoior reissue May 2 5, 1834, Serial No.

UNITED STATES' PATENT"OF FiCEf o Claims. i. 62-41 The invention relate's to artificial refrigeration earthenware, etc., may be substituted therefor. apparatus and has particular r'elation to an ap- An opening |4 for the introduction of the brine .paratus ot the above designated character which solution into the tank |3 is adapted to be closed shall be especially applicable foroperation autoby `a, suitable cap IG. A metallc sleeve or heat 5 matically when' a warm 'freezing tray is inserted exchanger l 1, projecting internally of the tank l3, therein. I is adapted to receive and support a freezing tray An object of the invention is to provide a. refrig- |8 for containing water or other substances which erant -liquid evaporating' unit having an expanare required to be frozen. sion device associated therewith which is directly Refrigerant fluid, received under pressure :from

10 controlled as afunction 6: the temperature of the a compressor !8 andliquefied in a condenser-Zi, is atoresaid frezing tray. discharged from a liquid receiver 22 through a Another object of the invention isto provide a high pressure conduit 23 and conduit'coupling 25 I refrigeration apparatus a'pable of automatic opinto the high side of a refrigerant expansion valve eration in response to the .disposition of warm 24. Ahousing 26 comprisin'gr'a. portion of theexsubstances therein, which apparatus shall likepansion valve24 is provided with acentrally diswise be c'apableof employment in so-called multi posed opening 21 'at the innerend of whi'ch a ple unit sy tems, i sleeve 28 is threaded.- 'I'he' threade'd endof the The invention' is embodied -in a .refrig'eration sleeve also is provided with 'a'n' axially disposed i apparatus employing a fre'ezing trysleeve, the orifice 28,-in one extremity of' whicha 'valve 3| temperature oi' which controls the pre'ssure of a" is seated i 2 conflned and expansible fluid-for Operating an A' cylindrical extension portion 32 of, the valve expansion valve by which refrigerant liquid is ad 3| is disposed'in an opening formed axially in a mitted to a refrigerant evaporating unit assoslide member 33, the outer end of the cylindrical -clated with the sleeve. The operation of a conportion being adapted to` rest upon a spherical densing unit associated with the apparatus is I bearing 34 .which is seated in the bottom of the controlled by a, low-pressure-side controlling' deaforesaid opening. A spring 36 disposed within c vice the employment of which makes possible the the sleeve 28 is adapted to be compressed between multiple installation of apparatusof such charthe slide member 33 and a threaded disc 31 adacterin association with a single condensing unit. justably secured within the sleeve 28 at the outer For a better Understanding of the invention, end thereof. An* opening 30 formed c entrally of reference may now be had to the accompanying thedisc 31 provides for the admission of ref -igdrawing forming a part oi' this specioation in erant fluid to the interior of the sleeve 28. A which: i g stem 38 of the valve 3| projecting throughout the Flgure 1 is a i'ragmentary cross-sectional view orifice 28 is rigidly secured at the centre of a disc of a refrigerator cabinet embodying an evaporat- 38 which is located in a recess formed in the housing unit 'char`acterizi'ng one form which the ining 28 beyond the threaded end of the sleeve .28. vention may assume; I A metallic diaphragm 4| disposed concentrically Figure 2 is a longitudinal cross-sectional view relative to 'the disc 38 is soldered, as indicated at through the evaporating unit illustrated by Fig- 42, in an annular recessformed in the housing 28. 40 ure 1; A larger annular recess '43 disposed internally w Flgure 3 is a diagrammatical view illustrating of the edge of the diaphragm 4I and .communia con densing unit which may be embodied in an cating with the orifice 28 is provided with an outapparatus constructed according to the principles let duct 44 formed in a boss portion 48 'of.-the ot the invention; V i housing 28 by which portion the exp'ansion .valve 5 Flgure 4 is a cross-sectional view of an expan- 24 is bolted, as indicated ai; 41, to a boss '48 se- 45 sion' valve associated with the evaporating unit cured in an opening formed in the brine tank !3. illustrated by Flgures l and 2. i v v A casing 48 having a fiange 5I bolted, .as indi- An artificial refrigeration apparatus charactercated at 52, to the housing 28,' externally of the izingone form of the invention consists of a rediaphragm 4I, is provided with acentrally dis- 4 0 '-lgerator `cabinet ll in which a refrigerant :posed opening 53 in the outer end of which an evaporating unit I2 is supported in anpsuitable adjustable head 54 is threaded. Openings 56, ma'mer (not shown). u formed in the outer surface of the head 54, pro- A brine tenk 13 maybe associated with the vide means for adjusting -the latter by the em'- evaporating unit -or, 11' prererred, other suitable 'ployment of a suitable spanner wrench (not 55 'substances such as cast iron, aluminum copper. shown.)

An annular shoulder 51 formed on the interier surface oi' the head 54 is adapted rotatably to env 50 and confined between the annular shoulder 58 and an annular shoulder SI projecting from one end -of a block 62 against a central portion of the diaphragm 4! opposite the disc 39. A bellows 63, disposed within the opening 53 and surrounding the spring 60, is

soldered at opposite ends to the outer peripheral portlons of the shoulders 58 and BI.

A conduit 54, soldered as indicated at 56 the coupling sleeve 5.9, provides communication between theinterior of the bellows 63 and a tubular expansible fluid containing bulb 61 which likewise is soldered, as indicated at 58, to the central ;portiontof the bottom surface of the sleeve !1 within the brine tank 13. When the freezing tray s, containing a warm substance desired to be frozen, is inserted in the sleeve I'I, the expansion of fluidwithin the bulk 61 causes a suflicient increase in the pressure within a bellows 63 to displace the diaphragm 4 l, the disc 39, and the valve 31, against the resilient force of the spring 36 thus admitting refrigerant lquid p through the orifice 29, the annular recess 43 and into the duct 44. Hence, the liquid is conducted through a centrally disposed opening, into a refrigerant liquid which' is coiled. in spiral lower surface oi the-sleeve ll and soldered thereto as indicated atfl l.` The inner convolution 12 of the colled conduit 69 should be disposedin spaced evaporating'conduit 69 formation against the relation to the bulb S'i, as indicated at 13, in order to avoid materially cooling the bulb 51 during the ev'aporation offluid in the conduits& The dischargeend '1.4 of the conduit 69 is connected to an end portion of a larger evaporating conduit 18 disposed incsnuous convolutiohs throughout the upper regionsof the brine tank !3. A suction line 11 communicating with the opposite end of the coil 16 is adapted to connect the latter with the' *low side "lsof the compressor !9. v

A pair of' vertically disposed bame plates 19 are soldered, or. otherwisegrigidly Secured at their upper ends,- to the edges of the sleeve !1, thus preventing the escape of the brine solution within the tank-from beneath .the sleeve I'I 'when the temperature*ofsuch'solution is increased by the absorption ofheat from the tray 18 through the hat exchanger or bottomportion oi thesleeve l'l and the conduit 59.

. thee'xpansion valve i In; the operation ofthe invention, when refrigerant liqud is admitted to the conduit 68 through 24 in responsetoa predetermined 'temperature of the 'fluid contained in the bulb-61.`the evaporationof such fluid in the inner V convolutions of the coiled conduits 69 causes a substantial increase in the temperature of all of the` fluid embodied in the conduits 69, 1-6 and 11. In

response to a predetermined* increase in such i fluid pressure, a suction pressureucontrol device 'an electrical circuit Bl o! well knownconstruction is adapted to close 82 through a motor. 83 by la is driven. When, after a considerable period,

which 'the compressor the substanca contaned in the freezing tray s is substantially'or entirely frozen, the, conduction i of -heat to thebulb 51 will decrease `to such an extent that the fluid pressure within the bellows 63 is insuflicient to cause the admission of any suburges the letter resiliently h within i forme'd in the boss 48. v

Changer; a, ciated with trol device Bl thus opening the circuit through'the motor 83 and discontinuing the operation of the r condensing unit. These Operations constitute a complete refrigeration cycle which will be repeated at intervals whenever the temperature of the fluid in the bulb ELby reason of its absorption of heat, either from the ireezing tray !8,- or from the brine tank !3, increases cient to, cause the operation of the expansion valve Although the specification discloses only the preferred form of this invention, and describes in detail but a single application thereof. it will be apparent to those skilled in the art that the invention is not so limited but that various modifications and changes maybe made therein without departing from the spirit of the invention or from the scope of the appended claims.

I claim:

1. The combination with a refrigerant compressing mechanism having a low side pressure controller associated therewith of a refrig'erant evaporating unitcomprising a heat exchange plate for supporting a freezing tray upon the upper surface thereof, and means disposed in thermal. contact with the lower surface of the aforesaid plate for controlling the operation of the refrigerant .evaporating unit.

- 2. A refrigerant'evaporating unit comprising a ,brine tank having a ireezing tray 'supported by'a p evapor ating conduit disposed in thermal contact with the bottom of the sleevega hollow tube containing a thermostat actuating fluid soldered to the bottom of the sleeve in spaced relation to the aforesaidconduit, and means controlled by the expansion of the aforesaid fluid for controlling the expansion of refrigerant liquid into the refrig- .erant evaporating conduit.`

4. A refrigerant 'vaporating unit comprising 'a metallic heat exchange plate for supporting` a freezing tray on the uppe' surface thei-cof, a refrigerant thermal contact with the bottom surface of the plate, means for expanding refrigerant fluid into the aforesaid conduit, a second conduit communicating with the first for evaporating refrigerant fluid received from the latter, and an expansible fluid containing bulb in thermal contact with the bottom of the aforesaid plate for controlling the operation of the aforesaid expansion means.

5. Areirigerant evaporating unit comprising a metallic heat exchanger for supporting a freezing tray on the upper surface thereof, a refrigerant fluid evaporating conduit disposed in thermal contact with the bottom` of the, aforesaid beat exliquid heat retaining substance assoth'e aforesaid conduit and bottom of the heat exchanger,.means 'for preventing the circulation of the aforesaid substance under" the to a value suflifluid evaporating conduit disposed in influence of heat absorbed from the .heatexchanger and conduit, and means associated with the lower surface oi the heat exchanger for cona trolling the expansion of a reirigerant fluid in the tact with a freezing tray. means in themial con-' tact with the heat exchanger for evaporating-a refrigerant fluid, a' vaive ior controi1ing-the admission' of refrigerant fluid within the last mentioned means, and a conflned' expansibl'e fluid associated with the heat exchanger and the valve i'or`controlling the operation of the latter.

7. .A reirigerant evaporatinginit comprising a brine tank having a sleeve`projecting therein for supporting a ireezing tray, a reirigerant ev'aporating conduit solde'ed to the bottom of the sieeve, an expansion valve i'or the admis'sion of refrigerant liquid intothe eva'porating conduit. a conflned expansible, fluid associated with the evaporating unit for controlling the operation oi the aforesaid expansion valve. A

8. A refriger ant evaporating unit comprising a brine tani: havinga sleeve projecting thei-ein for ;supporting a freezing tray, a refrigerant. evaporating conduit soldered to the bottom of the sleeve, bame means projecting below the sleeve for conflning a prine solution therein'; an expension valve for the admission oi refrigerant iiquid into'the evaporating conduit, and a 'conflned expansible fluid associated with the evaporating 3 unit !or controiling the operation oi' the ai'oresaid expanion valve.

9.A rei'riger'ator -comprising in combination. a rei'rigerating compartment, in which air, is circulated, a heat abso'ber within the conpartment for cooling the air, an ice tray or the like intimately associated with the heat absorber, means V. for causing such circulation of reirigerant through ;the heat ahsorber so as to maintain the heat absorber between predetermined temperature limits at all times during normal operation, and another means for controling the circulation of ren-igr erant through the beat absorber, said last means including a' control thermostat disposed in intimate h`eat exchange relation with substanca in the tray. v

'10. A refrigerator comprising in combination, a

,reirigerating compartment, in which air is circulated, a, heat absorber within the compartment i'or cooling the air, an ice tray or the like intimately associated with the heat absorber, means for causing such circulation of retrigerant through the heat absorber so as` to maintain the heat absorber between predetermined temperatu'e limits at all times during normal operation, and a thermostat arranged in. intimate heat exchange relation with ,and responsive primarily to the temperature oi non-frozen substance in the tray, when the ti'ay is in position, for increasing circulation of refrigerant through'the heat absorber 'when the substance is in a non-rrezen V state.

LAWRENCE A. PIIILIPP. 

